[PATCH] D62791: [CFLGraph] Add support for unary fneg instruction.

Mon Jun 3 07:39:12 PDT 2019

cameron.mcinally added a comment.

I don't know much about this pass either, but it looks like `test/Analysis/CFLAliasAnalysis` is the right place.

I hacked up `Steensgaard/constant-over-index.ll` to include an fneg and that seems to exercise the code. Your guess is better than mine if it's sufficient coverage or not.

  --- a/llvm/test/Analysis/CFLAliasAnalysis/Steensgaard/constant-over-index.ll
  +++ b/llvm/test/Analysis/CFLAliasAnalysis/Steensgaard/constant-over-index.ll
  @@ -18,7 +18,9 @@ loop:

     %p.0.i.0 = getelementptr [3 x [3 x double]], [3 x [3 x double]]* %p, i64 0, i64 %i, i64 0

  -  store volatile double 0.0, double* %p3
  +  %neg = fneg double 0.0
  +
  +  store volatile double %neg, double* %p3
     store volatile double 0.1, double* %p.0.i.0

To be clear, I'm not suggesting that as a test -- just proving that the new code is exercised with this change.

Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D62791/new/

https://reviews.llvm.org/D62791